1. Field of the Invention
The present invention is directed to a shock wave source of the type suitable for treating calculi in the body of a patient, and in particular to a shock wave source operating on the principle of rapid electromagnetic repulsion of a membrane to generate shock waves.
2. Description of the Prior Art
Shock wave sources are known in the art which generally include a shock wave tube filled with a shock wave propagating medium, such as water, with one end of the tube being closed by a flexible sack which can be pressed against the patient, and an opposite end closed by an electrically conductive membrane. The membrane is disposed opposite a coil, and is separated therefrom by an insulating layer. The coil is connected to a supply which generates high voltage pulses.
A shock wave source of this type permits the generation of focused shock waves, which can be directed to a calculus to be disintegrated, for example a kidney stone, the action of the shock waves on the calculus pulverizing the calculus to such an extent that the particles can be naturally eliminated. Shock wave generation occurs by the application of a high voltage pulse to the coil, which may be a spiral winding, so that an electromagnetic field is generated which causes the membrane to be rapidly repelled, thereby generating a pressure pulse which is converted by a focusing means into a shock wave, which is directed to the calculus.